Sun Position Solstice and Equinoxes

On the Physical Geography entry on the popup menu after right clicking on the map.

This diagram shows a polar plot, with the azimuth to the sun along the spokes of the diagram, and solar altitude from the small circles.

Noon will be when the sun reaches its highest altitude, the point closest to the center of the diagram. 

The curve farthest north will be the June Solistice, the farthest south will be the December solstice, and the two equinoxes will be identical and between the solstices on the diagram.

The sun can only get directly overhead at positions between the two tropics.  At the tropics it will be overhead only at a solstice; other locations between the tropics will have it overhead on two days, which at the equator it will be overhead at  the two equinoxes.

On the equinoxes, everywhere on earth the sun will rise due east and set due west.

You can compare these with the variation in daylight duration.  Incoming solar radiation, which affects climate and vegetation, depends on the duration of sunlight, the altititude of the sun, and the presence of clouds.

Point just inside the arctic circle. 

  • At the June Solstice, the sun never sets and complete a full 360 degree transit.
  • The two equinoxes (dark green) have the same pattern, with the sun rising in the east and setting in the west (true at any latitude), which happens everywhere on earth.
  • The sun never rises for the December solstice.

Annapolis at 39 degrees north.
 

  • At the June solstice (blue), the sun rises in the northeast (60 degrees)  and sets in the northwest (300 degrees).  It almost gets directly overhead at noon (actually about 75 degrees), at the Tropic of Cancer on this day the sun would directly overhead.
  • The two equinoxes (dark green) have the same pattern, with the sun rising in the east and setting in the west, which happens everywhere on earth on this day.
  • At the December solstice (cyan), the sun rises in the southeast (120 degrees) and sets in the southwest (240 degrees).  It gets to a maximum of 30 degrees above the horizon at noon.  Good time for photography.
  • The sun is always to the south at noon, which happens everywhere north of the Tropic of Cancer.

The equator

  • At the June Solstice, the sun is always to the north, and never quites get directly overhead.
  • The two equinoxes (dark green) have the same pattern, with the sun rising in the east and setting in the west, which happens everywhere on earth.  The sun is directly overhead at noon.
  • At the Decrmber Solstice, the sun is always to the south, and never quites get directly overhead.
  • The equator has 12 hours of sunlight every day of the year.

If requested, today's positon will be shown in red, and will be between a solstice and an equinox. 

Last revision 1/5/2020